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Background and objective: One of the functions attributed to the auditory efferent system is related to the processing of acoustic stimuli in noise backgrounds. However, clinical implications and the neurophysiological mechanisms of this system are not yet understood, especially on higher regions of the central nervous system. Only a few researchers studied the effects of noise on cortical auditory evoked potentials (CAEP), but the lack of studies in this area and the contradictory results, especially in children, point to the need to investigate different protocols and parameters that could allow the study of top-down activity in humans. For this reason, the aim of this study was to analyze the effect of varying levels of contralateral noise on efferent activity in children by recording CAEPs with tone burst stimuli. Additionally, we aimed at verifying the effects of contralateral noise on cortical processing of speech stimuli. Methods: Monaural CAEPs were recorded using tone burst stimuli in quiet and with contralateral white noise at 60 dB and at 70 dB in 65 typically developing school-aged children (experiment 1), and using speech stimuli with contralateral white noise at 60 dB in 41 children (experiment 2). Results: In experiment 1, noise induced changes were observed only for P1 and P300 components. P1 latency was prolonged at both noise level conditions, P300 latency was prolonged only in the condition with noise at 70 dB, and P300 amplitude was reduced only in the condition with noise at 60 dB. In experiment 2, noise induced latency delays were observed on P1, P2, N2, and P300 components and amplitude reduction was observed only for N1. Conclusion: The effects of noise stimulation were observed on all CAEP components elicited by speech, but the same was not observed in the experiment with tone bursts. The study of noise effects on CAEPs can provide electrophysiological evidence on how difficult listening situations affect sound discrimination and stimulus evaluation at thalamocortical regions. [ABSTRACT FROM AUTHOR]

Introduction: Coronavirus disease 2019 (COVID-19) is an infectious disease caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), a new member of the coronavirus family. While respiratory transmission is the main route, concerns have arisen regarding possible vertical transmission, which refers to the transmission of the virus from mother to fetus through the dissemination of viral particles in the amniotic fluid. Fetal viral infection via the placenta can affect the formation of the auditory system and lead to congenital hearing disorders. The aim of this research was to investigate the effects of vertical exposure to COVID-19 on the auditory system of newborns. Methodology: The study included a study group (SG) and a control group (CG). Selected during neonatal hearing screening, the SG consisted of 23 infants up to 1 year old whose mothers had been infected with SARS-CoV-2. The CG consisted of 15 infants whose mothers became pregnant after the end of the pandemic, had tested negative for COVID-19, and had no respiratory symptoms during pregnancy. The assessments for both groups were brainstem auditory evoked potentials (BAEPs), tympanometry, transient evoked otoacoustic emissions (TEOAEs), and distortion product otoacoustic emissions (DPOAEs). The research was divided into two studies, one cross-sectional and the other longitudinal. Results: All participants exhibited absolute latencies within the normal range for waves I, III, and V, although in the SG, there was a statistically significant increase in the latency of wave I in the left ear. In terms of OAEs, in the SG, there appeared to be a tendency for TEOAEs to be absent at high frequencies. Over several months, there was a general decrease in the amplitude of high-frequency responses in both TEOAEs and DPOAEs. Conclusion: No evidence was found that vertical exposure to COVID-19 causes hearing loss, although there were signs of possible deterioration in hair cell functioning. [ABSTRACT FROM AUTHOR]

COVID-19 is an infectious disease caused by the SARS-CoV-2 virus. During and after COVID-19, audiovestibular symptoms and impairments have been reported. Objectives: This study aimed to investigate the impacts of COVID-19 on the peripheral and central auditory systems of children and adolescents following the acute COVID-19 phase based on behavioral, electroacoustic, and electrophysiological audiological assessments. Methods: This is a primary, prospective, observational, and cross-sectional study of 23 children aged 8 to 15 years who acquired confirmed COVID-19 and who, before infection, had not had any auditory complaints or school complications. The results were compared with pre-pandemic data collected from a similar group of 23 children who had normal peripheral and central hearing and good school performance. Each participant answered a questionnaire about child development, school, and health history and underwent tests including pure-tone audiometry and high-frequency audiometry, imitanciometry, transient evoked otoacoustic emissions, and distortion product otoacoustic emissions. They also received tests of Brainstem Auditory Evoked Potentials, Long Latency Auditory Evoked Potentials, Dichotic Digits Test, Sentence Identification Test, Dichotic Consonant–Vowel Test, Frequency Pattern Test, and Gaps-In-Noise Test. Results: Significant differences were observed between the groups, with the study group showing worse thresholds compared to the control group at both standard audiometric frequencies and at higher frequencies, although both groups were still within normal limits (p ≤ 0.05). In addition, the study group had a higher prevalence of absent responses, as identified by otoacoustic emissions and acoustic reflexes. In terms of central auditory performance, the study group showed ABRs with significantly longer latencies of waves I, III, and V compared to the control group. The study group also performed less well on the Dichotic Digits and Pediatric Speech Identification tests. Conclusions: COVID-19 appears to alter the auditory system, both peripherally at the level of the outer hair cells and more centrally. [ABSTRACT FROM AUTHOR]

Background: The objective was to analyze wideband acoustic absorbance and transiently evoked otoacoustic emissions (TEOAEs) from newborns without risk indicators of hearing loss and test the effectiveness of measuring TEOAEs under pressurized ear canal conditions. Methods: Evaluation of 102 newborns from a maternity hospital, who stayed in the well-baby nursery and did not have risk indicators for hearing loss. The procedures involved wideband tympanometry and TEOAEs performed at ambient pressure (AP) and at a pressure corresponding to maximum compliance (PP). Newborns were then divided into three groups according to their AP and PP results: G1 (PASS/PASS), G2 (FAIL/PASS), and G3 (FAIL/FAIL). Results: Comparing the three groups, pressurization improved the pass rate for G2 only. For wideband absorbance, differences were statistically significant for frequencies of 2, 3, and 6 kHz, with lower values under the AP condition. For TEOAEs, the differences were statistically significant in all bands, with lower values under the AP condition. Conclusions: Pressurization was effective in detecting more TEOAEs in G2, thus reducing the number of failures in neonatal hearing screening and reducing the need to return for retesting. [ABSTRACT FROM AUTHOR]

Background: This study examined the relationship between behavioural thresholds as measured by pure tone audiometry and electrophysiological thresholds measured by the Auditory Steady-State Response (ASSR) in children with normal hearing and sensorineural hearing loss. Materials and Methods: After being assessed, 45 children of both sexes, ranging in age from 5 to 15, were split into four groups: 10 with moderate to moderately severe sensorineural hearing loss (G2M); 10 with steeply sloping sensorineural hearing loss (G2D); 10 with profound and severe sensorineural hearing loss (G2S); and 15 with normal hearing (G1). ASSR, tympanometry, acoustic reflex testing, pure tone audiometry, and speech audiometry (SRT and SDT) were performed. Results: The electrophysiological maximum in the group with normal hearing thresholds varied from 19 to 27 dB NA. The correlation in the group with moderate to moderately severe hearing loss was 0.42–0.74. The correlation in the steeply sloping hearing loss group was 0.68–0.94. The correlation in the group of people with profound and severe hearing loss was 0.59–0.86. The normal hearing group's mean differences in ASSR threshold and audiometric threshold ranged from −0.3 to 12 dB, in the moderate and moderately severe hearing loss group from −9 to 2 dB, in the steeply sloping hearing loss group from 1.4 to 7.5 dB, and in the severe and profound hearing loss group from −0.40 to 8.5 dB. Conclusion: As expected, there was no strong relationship between behavioural and electrophysiological thresholds in the group with normal hearing. But in children with hearing loss, there was a strong correlation between electrophysiological and behavioural thresholds; this relationship was especially evident in children with severe and profound hearing loss and those with steeply sloping hearing loss. [ABSTRACT FROM AUTHOR]

Palatine and pharyngeal tonsil hypertrophy may lead to dysfunction of the auditory tube due to a propensity for infection, potentially giving rise to otitis media. This is a quantitative and longitudinal study, developed from 2019 to 2021, at the State University of Campinas (UNICAMP). The studied sample comprised 15 participants aged 5 to 12 years (mean 7.9 years), 12 male and 3 female, arranged into two groups: children diagnosed with pharyngeal and/or palatine tonsil hypertrophy who were candidates for surgery (G1), and children who were later evaluated after surgery (G2). As part of the test, an otoscopy and measurements of logoaudiometry, pure-tone threshold audiometry, wideband tympanometry (ambient and peak pressure), and otoacoustic emissions (TEOAEs and DPOAEs, both at ambient and peak pressure) were all performed. There were statistically significant differences between phases in pure-tone audiometry, in terms of 226 Hz tympanometry, wideband tympanometry in peak pressure conditions, in the amplitude measurement TEOAEs in both pressure conditions, in DPOAEs in ambient pressure conditions, and in the signal/noise measurement in both pressures in DPOAEs. Overall, it was found that hearing tests were different for subjects with palatine and pharyngeal tonsil hypertrophy compared to the post-surgical group. [ABSTRACT FROM AUTHOR]

Introduction Peripheral hearing loss, besides causing inadequate auditory input, can lead to distortions in the tonotopic auditory map and reorganization of neural networks. Therefore, the processing of temporal aspects of a sound stimulus and, consequently, the effectiveness of human communication can be negatively impacted. Objective To test the temporal ordering and auditory resolution of people with mild and moderate sensorineural hearing loss and to compare them with the those of people with normal hearing. Methods A total of 19 right-handed individuals aged 16 to 59 years with mild to moderate postlingually acquired symmetric bilateral sensorineural hearing loss participated in the study. They were submitted to frequency and duration pattern tests and a random gap detection test. Results The mean correct response rate in the frequency pattern test was of 66.3%, and, in the duration pattern test, 71.7%. The mean threshold in the random gap detection test was of 14.1 ms. A comparison with the criteria established for normal subjects without peripheral hearing loss revealed that more than half the subjects had abnormal results in the temporal ordering test, while a smaller fraction had reduced temporal resolution. Conclusions The performance of the subjects with acquired sensorineural hearing loss was poorer than that of the participants without peripheral hearing loss. Their results on the temporal ordering test were also poorer than in the temporal resolution test, demonstrating the importance of analyzing both these auditory skills in people with peripheral hearing loss. [ABSTRACT FROM AUTHOR]

Introduction Auditory evoked potentials are widely used in clinical practice to complement the assessment of central auditory processing. However, it is necessary to understand whether these potentials are highly accurate, to assist in the diagnosis of auditory processing disorder. Objective To measure the accuracy of middle and long latency auditory evoked potentials in the diagnosis of auditory processing disorder in adults. Methods This is a case-control study, formed by a control group of 30 individuals with normal auditory processing assessment, and a case group composed of 43 individuals with altered auditory processing assessment. Their sensitivities, specificities, accuracies, positive and negative predictive values for the diagnosis of alterations were measured and compared between the potentials. Results The accuracies of the middle and long latency potentials were 51% and 67%, respectively. The P1-N1-P2 and N2-P300 complexes had an accuracy of 57.5% and 58.9%, respectively. The cognitive potential P300 showed an accuracy of 55%. There was no significant result for the middle-latency potential (OR = 1.8; 95% CI: 0.6–5.4, p > 0.42) and for P300 (OR = 2.63, 95% CI: 0.85–8.43, p > 0.11). However, the result was significant for the long-latency potential (OR = 6.3; 95% CI: 2–19.6, p < 0.01). There was a significant result for the P1-N1-P2 complexes (OR = 6.76, 95% CI:1.4–32.5, p = < 0.010) and N2-P300 (OR = 3.60; 95% CI: 10.16–11.20, p < 0.039). Conclusion Individuals with altered long-latency auditory evoked potential are more likely to have auditory processing disorder and, as such, this test can be used as a complementary tool to confirm the diagnosis. [ABSTRACT FROM AUTHOR]